package TestA;

public class Test {
    public static void main(String[] args) {
        //Dog dog = new Dog("小黑",3);
        //Cat cat = new Cat();
        Animal a = new Cat();
    }
}

class Base {
    Base() {
        System.out.print("Base");
    }
}

class Alpha extends Base {

    public static void main( String[] args ) {
        new Alpha();//1
        //调用父类无参的构造方法
        new Base();//2
    }
}